THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

JOSH LEVS, CNN CORRESPONDENT: But London's track record at blocking attacks, suicide or remote detonation, means a successful attempt can make a big statement. UNIDENTIFIED MALE: We have so much experience with terrorism fighting the IRA over 30 years that we -- this will be the place. If you can get through here, you can get through anywhere.

LEVS: And that's significant because what we're seeing today is in a way a reminder of that, that in a way Britain and the UK can be seen as a challenge by terrorists who want to prove that they can get through anywhere and it's also very significant to think about this history because what we're seeing here is the United States is actually taking a lot of lessons from Britain. But at the same time you can look at what happened in Glasgow today, how that car did get through and you can look behind me at Hartsfield Atlanta international airport and recognize that there are a lot of procedures that are in place here in the United States post-9/11 that now some other areas perhaps including Scotland, including the UK, will now start to copy from the United States. Melissa?

SUSAN ROESGEN, CNN ANCHOR, NEWSROOM: Here's what we know on the terrorist threat that's going on right now in the United Kingdom. Authorities are preparing for a possible other terror related incident. The British government has raised the UK's terror threat level to critical. That is its highest designation.

LONG: This after the arrest of two people following today's incident at the Glasgow international airport where that vehicle slammed into the terminal building and burst into flames. And that couples with yesterday's failed car bomb attack in London has British authorities believing both incidents are related.

ROESGEN: And now we want to check in with our Robin Oakley in London, CNN's correspondent in London to get the very latest on what's happening there. Robin, we heard earlier today the brief statement from the prime minister, Gordon Brown, has the queen or Prince Charles made any statement about what's happened?

ROBIN OAKLEY, CNN CORRESPONDENT: No, we've not heard anything from the royal family as yet, but of course there are a lot of events going on in London this weekend including the memorial concert for Princess Diana organized by her sons, the two princes, which a lot of people will be attending and obviously there will be a very big security alert around that. But for the moment all the comment has come from the prime minister and from the new home secretary, Jacqui Smith, the woman in charge of counterterrorism and crime and, as you said, the level of alert has been raised from severe to critical.

Now Britain, ever since the July 2005 bombings on the London subway has had that level of severe security alert which means that the definition there is that an attack is highly likely. Now they're saying that an attack is actually imminent and obviously the public have all been asked to be very vigilant in these circumstances and to report anything suspicious they see on the anti-terrorism hotline.

ROESGEN: Robin, after 9/11, this country was very eager to get back to normalcy. I remember we had the Super Bowl after 9/11 with tight security. We had a lot of major events, because people in this country said we refuse to bow to international terrorism. Is that the sentiment also in London and are these events, the Diana tribute and Wimbledon going to go on with that sort of sentiment or do you think that there could be a chance that the security forces just couldn't contain something that might happen and they might have to cancel or postpone them?

OAKLEY: Absolutely no possibility of them being canceled. Britain and London in particular has lived through terrorist attacks before, of course through the years of the Irish Republican army, and there's very much a public mood of not being deterred from going about their normal business. Ken Livingston, the mayor of London has urged people who were already intending to take part for example in the gay pride march or to go off to the Wimbledon tennis championships, to do exactly what they were going to do before but allow a little bit more longer in terms of their travel to and from the event because of the necessary restrictions with heightened security. But, no, life very much goes on as before Susan.

ROESGEN: And, Robin, back to the actual investigation into what happened today, Paula Newton, our CNN correspondent earlier told us the freshest information was that, though the police did not reveal it, CNN sources had told her that there was a third suspect in that burned out car, that the body was still in the car, there were three suspects, one severely burned in the hospital, one in custody, one dead. Have you heard anything else new, any more recent developments on the story, on the investigation?

OAKLEY: Nothing in terms of those kind of details that takes it on any further. What the police here are saying is that they have a wealth of evidence, certainly here in London, from those two car bombs that were discovered and the fact that neither of them proved successful, neither of them went off, has left them with the possibility of a lot of DNA evidence, a lot of fingerprint evidence, and evidence on the purchase of the materials used to make those car bombs, Susan.

ROESGEN: OK. Robin Oakley reporting live for us in London. Thank you, Robin. LONG: With the heightened security alert level in the UK at critical and airports closed, among them the Glasgow international airport and also the airport Liverpool John Lennon closed as a security precaution, solely as a security precaution. But because of that, obviously you have stranded passengers. We have one such passenger joining us on the line right now. That's Paul McDermott who is stranded outside of Liverpool's John Lennon airport. Paul, thanks so much for your time.

PAUL McDERMOTT: Yes, (INAUDIBLE).

LONG: So I understand you were traveling with a large group, about eight family members, on vacation, Majorca I believe was your destination.

McDERMOTT: Yes, that's right.

LONG: Take me through the steps when you arrived at the airport, when you heard the news about what was happening in Glasgow, and then take me from there.

McDERMOTT: Right. Basically we arrived at about 4:00 to check in. We (INAUDIBLE) proceed then towards check-out, to the baggage, went through (INAUDIBLE) just going through to passport control and then we got informed we had to evacuate the building. We got out of the building pretty quickly. It was protocol to cross over to a center, a sports center.

LONG: You are at the sports center now. How many other people are there with you aside from your eight family members?

McDERMOTT: 150, maybe 200. A lot of people have gone on that live local but the people that live a distance away like ourselves are having to stay the night here so at least 9:00, 10:00 in the morning.

LONG: It is just after midnight. You're going to be there through the early morning hours.

McDERMOTT: Yes.

LONG: What information have you been given and also what amenities have you been given? Do you have a place to rest?

McDERMOTT: Well, the Salvation Army have turned up with hot drinks and snacks and bringing beds and blankets around for the sports hall where everybody is going to sleep in a communal place, unfortunately.

LONG: And have you been given any information about when you may be able to fly to your ultimate destination?

McDERMOTT: No, not at the moment. Maybe 9:00 tomorrow morning, could be as late as 5:00, 6:00 tomorrow night. We don't know the definites as of yet.

LONG: Considering that, that is very much up in the air, do you have any plans to cancel your holiday?

McDERMOTT: No because I've worked hard all year for the holiday.

LONG: What will this do to your personal holiday? If you've been waiting all year, you don't have a lot of vacation time banked up either.

McDERMOTT: No. Two weeks in New York with my three daughters. My daughter's boyfriend, little grandson and it's just ruined it for us basically. We're going to lose two days of sunshine.

LONG: We've heard a lot of reports today that people from the UK are resilient. So considering that, what are your thoughts today with news of the thwarted bombings in London and today's fiery explosion outside of the Glasgow airport?

McDERMOTT: Devastated, actually. I mean, Britain is a good place to live but you have idiots like terrorists coming in and spoiling it for everybody.

LONG: Idiots, as you say, coming in and spoiling it for everyone, will this force you to change the way you live in the next coming days? You said you're not going to cancel your vacation, but the way you go about just your vacation, your daily comings and goings or the next couple of months?

McDERMOTT: Yes. I'll be very vigilant about people and watch for suspicious packages, suspicious people, cars, that type of thing.

LONG: And I guess my last question also has to deal with the fact that there are people that are still knowingly on the loose in the UK. I don't know exactly where you're from. I believe you're from Liverpool?

McDERMOTT: No, no Lancashire, Bolton (ph) in Lancashire.

LONG: What does that, how do you feel knowing that of course we have people that have been apprehended associated with the Glasgow incident, but there are people on the loose with the intent to cause harm in London.

McDERMOTT: Well, they're just animals is all I can say. There's no other word for them.

LONG: Paul McDermott, a stranded traveler at Liverpool John Lennon airport, an airport that has been closed as a security precaution. You're there at that sports center along with eight family members. I know you've been waiting all year for this vacation. I guess the good thing is that you're stranded with your family members.

McDERMOTT: Yes, we are.

LONG: Paul, thank you so much for your time. We appreciate. Take good care.

McDERMOTT: You're welcome. Thank you very much indeed. Bye-bye.

ROESGEN: Well, also on vacation, a mini vacation but following the events very closely is President Bush. He is at his family's estate in Kennebunkport, Maine this weekend and he's going to be meeting Russian President Vladimir Putin there tomorrow. CNN's Ed Henry is covering the presidential visit there in Kennebunkport. Ed.

ED HENRY, CNN CORRESPONDENT: Well, Susan it's interesting. As you noted, the president has been on vacation but he has been trying to be brief throughout the day and today he got several briefings on two situations both what had happened in London, those incidents yesterday as well as what happened today in Glasgow. Senior officials here say though that the Bush administration has decided not to lift the threat level in the United States, not follow the footsteps of the British Prime Minister Gordon Brown, what he's done there, because they do not have a specific credible threat against the United States.

One senior official also telling CNN that based on the intelligence the U.S. has gotten so far, they do not believe these incidents were quote unquote professional and also saying that they had some aspects of being amateurish, not sophisticated attacks, clearly not attacks or incidents of the scale of a 9/11. That's why the U.S. has been trying to keep some balance to it and not overreact to it. Instead what we're seeing is that the traveling White House is trying to keep on top of the situation. Homeland security officials around the president are giving him regular updates to make sure he's aware of the situation but, again, they have decided to not, for now, lift the threat level but they're taking it seriously enough that the Transportation Security Administration has decided to send out basically bulletins, alerts to airports all around the United States, similar to what Robin Oakley was saying they're warning U.S. travelers, just as British travelers are facing, there will be some delays at U.S. airports, that there will be more of a police presence outside especially major airports, New York, New Jersey, Los Angeles airport as well as we've heard anecdotally.

Finally there have been a lot of questions about why President Bush has not called Gordon Brown yet. As you know he's only been in office for a few days. So far White House officials are saying they don't want to escalate the situation by having a phone call between the president and the prime minister just yet. Instead at lower levels they've made it clear U.S. government officials calling British government officials and saying anything at all the British government needs in any of these incidents to get to the bottom of them, U.S. homeland security officials. FBI officials and others are willing to do anything they can to help.

ROESGEN: And, again, as we just mentioned, we've got Russian President Vladimir Putin coming tomorrow but they've got a whole different event -- agenda on their hands besides international terrorism.

HENRY: Absolutely. The point here is that President Bush invited President Putin to Kennebunkport for two days of talks. They're trying not to call it a summit, just saying they want it to be informal. That's exactly why Mr. Bush picked Kennebunkport where his family compound of course is here at Walker's Point. He wants to try to calm the relationship down. As you know at the beginning six, seven years ago, Mr Bush famously said that he had looked into Mr. Putin's eyes and seen into his soul and that he could trust him. In recent years there have been suggestions that trust has obviously been tested. Specifically there's been deep concern over a controversial U.S. plan to build a missile defense shield in Europe that Mr. Putin is not happy about. He's threatened to aim nuclear weapons at Europe in retaliation. So this next two days of talks will be all about trying to calm this relationship down, patch it back up. As you can imagine, given everything that's happening around the world, it's going to be heavy, heavy security presence. Here in Kennebunkport you essentially have three presidents, President Putin, the current President Bush, as well as President Bush's father, the former U.S. president. He's hosting these two days of talks, Susan.

ROESGEN: OK. Thank you, Ed Henry, for that report there in Kennebunkport, Maine.

LONG: This weekend CNN's specials investigations unit on the heels of the story in Glasgow and potentially deadly plot in the heart of London. CNN's Christiane Amanpour is uncovering terrorists' surprising new breeding ground where young British Muslims are being indoctrinated into extremism. It's a report only CNN could bring you. "The War Within," that is tonight and tomorrow night at 8:00 p.m. Eastern.

This car, an SUV, exploding outside of Glasgow's international airport, 3:15 local time. It's now after midnight in the UK and because of this, we have a heightened terror alert at the level of critical in the UK. No one was hurt. That's the good news. From the constable of the (INAUDIBLE) police, this is a horrendous criminal act felt by every member of our community. We are following this story from all angles. You're watching CNN.

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ROESGEN: One suspect dead, one in critical condition, and one more in custody. Apparently we've learned that there were at least three people involved in today's terrorist incident in Scotland. Chief Constable William Rae of the Scottish police had this to say about the one suspect who was badly burned and yet still alive and apparently still dangerous.

(BEGIN VIDEO CLIP)

CHIEF CONSTABLE WILLIAM RAE, STRATHCLYDE POLICE DEPT: At the scene has been detained and in police custody. The vehicle involved is still at the location. It is in a highly unstable condition and police officers have had to await clearance from colleagues and other (INAUDIBLE) before making an approach. As a consequence of that we had to evacuate the airport and a number of passengers have been left on aircraft on the tarmac. Our primary concern was their safety. And it would have been unwise to evacuate them into (INAUDIBLE) building. We realize the inconvenience and discomfort this has caused, but it was their safety that was our paramount concern.

(END VIDEO CLIP)

ROESGEN: Now in questioning by reporters, the constable says that the one suspect who was badly burned and who is still in the hospital in critical condition was wearing some sort of explosive device. He wouldn't call it a suicide belt, but he said it was threatening enough that they had to evacuate part of the hospital to get this explosive device off that suspect. Once again that suspect is in critical condition at the hospital. Another is under arrest, in custody, and then we later learned that there was a third person involved and that that body is still in that car that they have still not yet removed from the airport in Glasgow.

LONG: And because of the incidents in London and Scotland today, it has really created a ripple effect on security measures here in the U.S. CNN's Jim Acosta is one of the correspondents stationed at airports around the country. He joins us now live from New York's la Guardia airport. Jim?

JIM ACOSTA, CNN CORRESPONDENT: Hi, Susan. Yes, we're at la Guardia airport in New York City and from what we've seen throughout the day it was a measurable uptick in security but nothing major in terms of flight delays, for people hurrying off to their busy July 4th holiday vacations. You can just look behind me right now. This is basically how it's been throughout the day. We've seen cars pulling up to the terminal dropping off loved ones and so forth and then throughout the day, we must say, that this is somewhat unusual. We have seen a greater police presence in terms of officers hustling people through here very quickly so they don't linger too long front of these terminals because literally -- and we've seen it -- you and I have both seen it at countless airports across the country, you can literally pull your car up in front of the terminal, in front of the front door, drop people off and send them on their way and today, and I think at this airport, airports throughout the country, what we've seen is the police departments at these various facilities saying, OK, wait a minute. We can't let folks linger in front of these facilities all day long like they may in certain situations and certain times of the day.

Earlier in the day we did see a greater police presence here. The New York police department's Hercules units showed up here at la Guardia airport. This is something that New Yorkers are familiar with. They'll see them on the streets of Manhattan where you see a dozen or so patrol cars sort of racing around the streets of Manhattan with their lights on to show that beefed up police presence that we've gotten used to, gotten accustomed to here in New York since September 11th. All in all this has been almost another day at the airport here in New York City. While passengers haven't been greatly inconvenienced, they have seen a slight uptick in the security presence here at the airport. Susan?

LONG: Jim Acosta reporting live for us at la Guardia airport. Thank you.

ACOSTA: You're welcome.

LONG: And we will have much more ahead. Again, this is the scene earlier today. An SUV on fire at the Glasgow airport in Scotland. One suspect in custody, one dead, one in critical condition. We'll have the latest on this and how it is linked to the foiled car bomb threats in London on Friday. Stay with us. You're watching CNN.

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ROESGEN: Some of the pictures there from the incident today at the Glasgow Scotland airport that has really been a crisis for the new British Prime Minister Gordon Brown. As we mentioned he's only been on the job less than a week now, but he knew that he had to talk to the British people after the incident today in Scotland and this is what he said just coming out of an emergency meeting with his security team.

(BEGIN VIDEO CLIP)

GORDON BROWN, BRITISH PRIME MINISTER: I've just come from a meeting with the police and with the security services and with the home secretary and government ministers and let me first of all thank the police, security services, all the emergency services for the dedicated professionalism that has been shown in responding to the incident yesterday in London and now today the attack at Glasgow airport. The first duty of the government is the security and safety of all the British people. So it is right to raise the levels of security at airports and in private places in the light of the heightened threat. I want all British people to be vigilant and I want them to support the police and all the authorities in the difficult decisions that they have to make. I know that the British people will stand together united, resolute, and strong.

(END VIDEO CLIP)

ROESGEN: This weekend on CNN specials investigation unit, on the heels of the story in Glasgow, the potentially deadly plot in the heart of London. CNN's Christiane Amanpour uncovers terrorists' surprising new breeding grounds where young British Muslims are being indoctrinated into extremism, a report only CNN could bring you, "The War Within." That's tonight and tomorrow night at 8:00 p.m. Eastern.

Who is responsible for the foiled bomb attacks in London yesterday and today's fiery crash at Glasgow's international airport? We're piecing together the terror incidents live in the CNN NEWSROOM.

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ROESGEN: Here is what we know on the terror threat going on right now in the UK where authorities are preparing for another possible terror-related incident. The British government has raised the UK's terror threat level to critical. That is the highest designation and this after the arrest of two people following today's incident at the Glasgow international airport where a vehicle, this SUV, slammed into a terminal building and burst into flames. CNN has learned one suspect has died, one is in critical condition with severe burns at a hospital and a bystander was also injured, a leg injury. Now all of this coupled with yesterday's failed car bombing attack in London has British authorities believing both incidents are related. Now the Glasgow attack has led the U.S. to beef up security. Lisa Goddard is monitoring the changes at Reagan National Airport right near the nation's capital. Lisa?

LISA GODDARD, CNN CORRESPONDENT: That's right. We've seen in the last couple of hours really a slight increase in security. Of course, who knows what they're doing behind-the-scenes as Homeland Security Secretary Michael Chertoff said the increased security at American airports will not all be visible.

I'll tell you what we've seen here at National, we've seen some increased foot patrols, we've seen a K-9 unit, we've also seen one of those two-wheeler Segways, an officer on that, specifically patrolling the drop-off area which is really just a few feet away from me, very close to the doors to the airport. But that drop-off area also has some large metal barriers that would make it impossible, officials say, for cars to come in here.

So clearly there has been increased security. Passengers are more and more aware as the day goes on of what happened in Scotland. Many of them are nervous. Those flying domestically seem have a different attitude, as we've talked about, than those internationally.

A very interesting story. We ran into two sisters. One of the sisters is trying to fly home to London, plans to fly home to London next week. The other sister was supposed to go with her. Here is how they reacted and what their plans are following today's events.

(BEGIN VIDEO CLIP)

UNIDENTIFIED FEMALE: Of course you do what you've got to do. I have to travel so I haven't got much choice but obviously it is worrying.

UNIDENTIFIED FEMALE: I was supposed to be going back with her on Monday -- I mean on Friday. I'm not going. I told her I'm not going. Right, because of that.

GODDARD: Tell me how you came to that decision exactly.

UNIDENTIFIED FEMALE: I don't want to be there and live in fear when I get there because I was going to be spending two weeks there and I know I wouldn't want to come out of the house, and so I decided I'm going to stay right here.

(END VIDEO CLIP)

GODDARD: She didn't want to live in fear so she's postponing a long-planned trip to London. Now a very different reaction from Americans we talked to. Listen to what this woman from Raleigh, North Carolina, says.

(BEGIN VIDEO CLIP) UNIDENTIFIED FEMALE: I fly all the time with my job. I fly around the country so I've gotten used to the threat. It's just part of what I take on with my job so I feel that if it's going to happen to me, it's going to happen to me on the street or in an airplane or wherever it might be. I do think that we've tried to do as much as we can.

(END VIDEO CLIP)

GODDARD: And, Melissa, I'll show you again what it looks like here at Washington National. What's been a quiet day pretty much all day long is now honestly becoming sleepy. There are not as many passengers anymore. The lines that we've seen which never were longer than a minute or two to get through security, sometimes there's no line at all. So really a calm attitude but we have seen an increased presence of officers. I wouldn't say a huge force but certainly notable. Melissa?

Joining us now from Reno, Nevada, by telephone, the former acting director of the CIA, John McLaughlin, he is CNN's national security analyst. Thanks so much for your time for joining us once again. We appreciate it.

JOHN MCLAUGHLIN, FORMER ACTING DIRECTOR OF THE CIA (on phone): Hello, Suzanne (ph).

LONG: Let's pick up where the conversation left off a couple of hours ago and talk about the marks of al Qaeda, whether or not this is, in fact, a terror attack, a terror foiled plot related to al Qaeda.

LAUGHLIN: As you know the details are still very sketchy. If you were trying to pick out things here that would have an al Qaeda signature at this point perhaps the most important thing would be the fact there was coordination apparently planned here between two sites, Glasgow and London. There were three vehicle bombs of different kinds and the vehicle bomb now is, of course, the weapon of choice for al Qaeda in Iraq. It isn't a bomb they've used many places elsewhere in the world, but that of course would be one thing that we have to think through here. Al Qaeda in Iraq is training a new generation of terrorists to operate in urban environments.

And we've been waiting for the tactics to show up in an urban environment. Superficially it would appear that might be a possibility here. It's too soon to identify this with any confidence as an al Qaeda operation but, as I said in the earlier interview, if you're British and you're looking at this as a security official, that's the thing you're going to be trying to prove or disprove given that the recent events of the terrorist nature in London have been al Qaeda related and linked to the leadership in Pakistan.

Now because of those events, this could have inspired local groups to copycat. They've heard about that. They see Iraq on television. They know from the publicity of the trial of a previous arrested terrorist who is in jail now who planned vehicle bomb attacks in London. They know that was a tactic. So possible we're seeing copycat here by a local inspired group, but that doesn't make it any less dangerous or worrisome for the British.

In fact as one of the British commentators pointed out today, that could make it worse because it would mean there's someone there they don't know about.

LONG: So essentially you're saying there could be still a domino effect to happen after today's fire explosion?

MCLAUGHLIN: There may be other things planned. That would be another al Qaeda hallmark. Typically they would have a plan that would involve more than one attack. The fact that there were a couple here.

The other thing to keep in mind is the British have said publicly that there are somewhere between 25 and 30 plots they're following and so, therefore, if we see this as one or two of those, it's quite conceivable that, we know as a fact there are other plots that could unfold related to this. Again if you were there, you got to assume this is going to happen again tomorrow somewhere. It may not but that's the assumption you have to work on as a security official.

LONG: John, with the fact that there were no explosions yesterday, with the fact the bombings were thwarted, would that anger the terrorists?

MCLAUGHLIN: Oh, yes. Yeah. They would -- and they would also be worried. Here's the other thing that they've got to think about now. Had these bombings been successful, the forensic evidence would have been much less, obviously a charred and destroyed vehicle.

Because the bombs didn't go off, I am very confident, very confident, that the British, given their skill and experience, will have forensic evidence here that will allow them to break this case. So if you're a terrorist and you are responsible for this, you're scared right now and you may be on the run. If you're on the run, you're more vulnerable to capture or detection.

And if you're not on the run and you're sitting tight somewhere, the circle may close around you. Because of the forensic evidence that's going to be plentiful in those two cars. As one of your earlier guests said, or one of the British said, there will be fingerprints, there will be DNA. They probably left behind carelessly some scrap of paper or something that they assumed might have been incinerated in the blaze.

And forensic science is such today that they're not only angry but I would say scared at this point.

LONG: That's CNN national security analyst, former acting director of the CIA, John McLaughlin. Thanks so much, John, for once again providing your expertise and your knowledge. We appreciate it.

MCLAUGHLIN: You bet. Thank you.

LONG: You're looking right there at pictures from Glasgow International Airport. This was hours ago, 3:15 local time is when this SUV, a Jeep Cherokee, careened into that vehicle causing today's chaos, causing the British government to increase the terror alert level to critical. This is a developing story we're continuing to follow for you in the NEWSROOM this year.

(COMMERCIAL BREAK)

(BEGIN VIDEO CLIP)

UNIDENTIFIED FEMALE: Did hear a blast. Sort of a bomb or something, like something explode. I heard one and I couldn't hear anymore.

(END VIDEO CLIP)

LONG: Witnesses at Glasgow International Airport today. Here is what we do know about the terror threat that's ongoing in the U.K. Authorities are prepping for another possible terror related incident. The British government has increased the U.K.'s terror threat level to critical, that is the highest designation.

This after the arrest of two people following today's incident at the airport in Glasgow where that vehicle right there slammed into the terminal building and burst into flames. One suspect died in the vehicle.

Now all of this coupled with yesterday's failed car bombing attacks in London has British authorities believing both incidents are related. Now, again, we have a heightened terror alert level in the U.K. There has been no change here at home in the U.S., but you will likely notice some stepped up security at airports.

Of course it is a busy travel season with the Fourth of July holiday on Wednesday. Josh Levs is at one of the busiest airports in the country, even in the world, that's Atlanta's Hartsfield Jackson Airport.

Hi, Josh.

JOSH LEVS, CNN CORRESPONDENT: Hey there. Yeah. It's actually the world's busiest passenger airport. Now I want to put this in context for all of you. We were talking earlier today about the size of the Glasgow Airport where the incident occurred today, 8.8 million passengers a year, I believe. Multiply that by 10 to get the airport behind me, Hartsfield-Jackson Atlanta International Airport.

Last year 85 million passengers came through here, nearly 100,000 take offs and landing. The world's busiest passenger airport which means more people going in and out all across the year.

So we came here to look at what's going on with security today. Now police didn't say specifically anything being done differently but the TSA did. What the TSA told us they've stepped up curbside presence today, and we actually saw that. We saw some members of the TSA doing what appeared to be sweeps along the curb which is right behind me here at the North Terminal.

Now I'll also tell you this airport has some pretty extensive procedures already in place to prevent any cars from being able to do the kind of thing that we saw in Glasgow. Cars are scoped before they even get close to the airport from aerial view. Once they do get up here they are not allowed to spend very long here and they cannot be unattended. There are a lot of people are watching all of the cars here all the time for just that reason. Security concerns. A lot of that put into place after 9/11.

There's also something else we found today. A man who had traveled in from London who told us how security at the London airport at Heathrow is different today.

(BEGIN VIDEO CLIP)

UNIDENTIFIED MALE: It was more than when we came into London about two weeks ago, so it was noticeable. There were police officers above us with guns on -- at the upper levels, so that was more noticeable. I didn't notice that when we came in.

(END VIDEO CLIP)

LEVS: And obviously there have been these changes at Heathrow and at other airports all over the world. Now on the inside of this airport, similar to what we're hearing at other U.S. airports, no tremendous -- no visible changes on the inside. The security lines I've seen that we've seen going to the planes are just about as long as they usually are, sometimes longer than what I've seen today. We spoke to some people on the inside who told us it doesn't make them specifically more concerned really about travel on an airplane itself because of what we saw today was not, Melissa, was not an attack on a plane.

LONG: And our coverage tying in with a special tonight, actually starting in just 15 minutes, CNN SPECIAL INVESTIGATIONS UNIT on the heels of the story in Glasgow, the potentially deadly plot in the heart of London. CNN's Christiane Amanpour is uncovering terror's surprising new breeding ground where young Muslims are being indoctrinated into extremism. It's a report only CNN could bring you, "The War Within." That is tonight and tomorrow night at 8:00 p.m. Eastern Time.

About 10 hours now since this fiery crash at the Glasgow International Airport, a busy airport used by more than 8 million passengers a year. The prime minister in his first few days in office has elevated the terror alert level in Great Britain to its highest level, critical.

This is a developing story. We're covering all the angles and bringing them to you as soon as that information is available.

You're watching CNN.

(COMMERCIAL BREAK)

LONG: Want to give you information just in to us here at CNN. According to the Associated Press, two people have been arrested in a northern part of England with some sort of a connection to the terror plots in London and Scotland.

Again, this is according to the Associated Press, two people have been arrested. CNN is working right now to independently confirm this latest report.

Now as you know, you are looking at video right now of that SUV that careened into terminal one at Glasgow's International Airport earlier today, 3:15 local time. It is now the early morning hours in Scotland. And of course we had the thwarted bombing attack yesterday in the U.K., in the heart of downtown London.

An unknown number of suspects associated with the thwarted bombing attacks. And today we've learned that there are, in fact, three known suspects associated with this attack. Two people in custody, one getting care at a hospital for severe burns. One person in police custody and the other person is, in fact, dead. A body found in that SUV.

So, again, that's the basic information. This just in to us here at CNN. The Associated Press reporting two more people have been arrested in Northern England in connection to the terror plots in the U.K. in both London and Scotland. That brings the total to four known persons arrested in connection with the terror plots.

As we get more information or CNN is able to confirm this, we will bring it to you this evening. Now has the U.K. been relatively lucky or have the incidents in London and Glasgow been carried out by bush league terrorists? I spoke with John Pike from globalsecurity.org and now he is going to share his thoughts on both failed terror attempts and who might be behind them.

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JOHN PIKE, GLOBALSECURITY.ORG: It's beginning to come into focus that if you have three people in the vehicle that if you had gasoline but no other explosives, maybe the plan was to go in and drive up to the security barrier and dump out all this gasoline all over the place and set it on fire.

It is sort of out of pattern here, a little difficult to connect the dots that we have one vehicle today with three people in it. Yesterday two vehicles with no people in it. What you really have to wonder is what we're going to see tomorrow and the next day.

LONG: I can sense your skepticism and at the same time you have different eyewitness reports saying will were small explosions coming from the car. We don't know there was nothing else in within that SUV.

PIKE: This is the puzzlement, of course, that we are getting conflicting reports. What we did not see, though, is the really large explosion you would have seen from those two car bombs the way they were built yesterday. So it's not exactly the same sort of explosive device that we were seeing yesterday.

LONG: So at the same time, though, authorities are saying the two are in fact linked but you're saying they seem to be totally different in their nature.

PIKE: Well, they're physically different but you think for them to be taking place this close to each other you would have to believe that they would be linked and you would have to be concerned the people who put together the car bombs yesterday, I don't necessarily assume, were in this vehicle today, that you're going to have additional conspirators who are at-large, the possibility of additional attacks that would also be different from these two in the next several days ahead.

LONG: We do have information stating today that the two Mercedes, the sedans, were in fact traced back to Glasgow. What do you think about that?

PIKE: Well that would suggest the possibility at least that we've got one and the same plot here. But again I think it's interesting we have not had had any additional arrests yet and that the authorities are not telling us an awful lot about what they had or had not learned from the car bombs yesterday.

LONG: Prior to the incident today at Glasgow, there were some that said the two thwarted bombings in London had the markings of al Qaeda. Do you think that?

PIKE: Well, it's difficult to say. Certainly we had previous thwarted attempts in which there had been plans to use propane tanks, plans to attack these public facilities. We've seen public facility attacks, restaurant, disco attacks in a number of other countries and so that would be within this larger pattern of al Qaeda.

Of course what direct physical connection these individuals, these attacks would have to Osama bin Laden is a completely different question.

LONG: Just a few days in office, the new Prime Minister Gordon Brown beset with awesome challenges. For that new prime minister and his newly appointed Cabinet as well dealing with terrorism threats. You're looking at video from the explosion at Glasgow's International Airport 3:15 local time today. It's now after midnight in London. You're watching CNN, the most trusted name in news.

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UNIDENTIFIED FEMALE: We saw the flames like coming out. And there were a lot of police and like ambulance like round people so we couldn't see the people that were there.

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LONG: Here is the latest on the terror threat in the U.K. British authorities have arrested two more people in connection with the terrorist incidents in England and Scotland. The British government raising their terror threat level to critical, the highest designation.

Now today at Glasgow International Airport a vehicle, this SUV, slammed into the terminal building, bursting into flames. Two suspects from that are in custody. A third reportedly died at the scene in the SUV.

Late word from CNN's Nic Robertson that some passengers at Glasgow's airport are now, just now, being taken often the plane and transported from the airport on buses.

We're going to get more information on that and bring it to you as soon as possible. Do keep in mind it was 3:15 local time when that SUV careened into the airport terminal. It is in the wee hours of the morning now. Many of those passengers, someone said possibly hundreds are trapped on the tarmac on the planes since then. We'll continue to follow their story.

Meantime, security has been beefed up at larger airports around the U.S. but the terror level in the U.S. remains unchanged. The new British Prime Minister Gordon Brown has been on the job four days and in less than a week a huge crisis. He spoke to the British people after another emergency meeting with his security team.

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GORDON BROWN, BRITISH PRIME MINISTER: I've just come from a meeting with the police and with the security services and with the home secretary and government ministers and let me first of all thank the police, security services, all the emergency services for the dedicated professionalism that has been shown in responding to the incident yesterday in London and now today, the attack at Glasgow Airport.

The first duty of the government is the security and safety of all the British people, so it is right to raise the levels of security at airports and in crowded places in the light of the heightened threat. I want all British people to be vigilant and I want them to support the police and all of the authorities in the difficult decisions that they have to make. I know that the British people will stand together united, resolute, and strong. (END VIDEO CLIP)

LONG: Gordon Brown, the prime minister of the U.K., just on the job some four days speaking to the British people, talking about that heightened level of terror. It is a critical level. Again, just on the job four days, also his Cabinet as well faced with some awesome challenges.

And this again just into us here at CNN, two more people arrested in conjunction with the attacks in London and in Glasgow. Two more people arrested in Cheshire, England in connection with the terrorist incident at the Glasgow International Airport today.

Also the discovery, of course, of those explosives laden cars in London in the wee hours earlier this week.

The arrests coming in addition to the two people arrested at the scene here at Glasgow's International Airport. There is still much more ahead on CNN. We will of course stay on the developing story out of England. A story now affecting secure concerns in the U.S. You can expect instant updates, live reports as the information becomes available.

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